l := list.concatenate(a<,idepth>)

Concatenates a nested iterable type into a single longer list.

The concatenation continues to a maximum nested depth of idepth. The type at each nested level of concatenation must be iterable. The default depth of concatenation is 1 unless otherwise specified.

For example a list of list of { {1,2,3}, {4,5,6}, {7,8,9} } can be concatenated into a single list { 1,2,3,4,5,6,7,8,9 }.

Returns:l - the list created from concatenating a nested sequence a iterable types together.
Arguments:a - the values use to create a list from. idepth - the nested levels to concatenate, or 1 if not specified.